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US5125963A - Metallurgical controlling method - Google Patents

Metallurgical controlling method Download PDF

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Publication number
US5125963A
US5125963A US07/772,115 US77211591A US5125963A US 5125963 A US5125963 A US 5125963A US 77211591 A US77211591 A US 77211591A US 5125963 A US5125963 A US 5125963A
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United States
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formed during
copper
species
pbs
slag
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Expired - Fee Related
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US07/772,115
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English (en)
Inventor
Lars E. M. Alden
Erik W. Persson
Erik W. Wendt
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Scandinavian Emission Technology AB
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Scandinavian Emission Technology AB
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Priority claimed from SE8703233A external-priority patent/SE458529B/sv
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B5/00—General methods of reducing to metals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32917—Plasma diagnostics
    • H01J37/32935—Monitoring and controlling tubes by information coming from the object and/or discharge
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B15/00—Obtaining copper
    • C22B15/0095—Process control or regulation methods
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
    • G01J3/28—Investigating the spectrum
    • G01J3/42—Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry
    • G01J3/427—Dual wavelengths spectrometry

Definitions

  • the object of the present invention is to obtain a possibility to control different smeltmetallurgical, endothermic and exothermic processes, particularly pyrometallurgical processes by spectrophotometry in a simple and rational way thus making it possible to improve the yield of the processes in a qualitative and quantitative way.
  • the flame present above the converter will look different, and thus it can not easily be determined visually, if, and when, the process is to be interrupted.
  • FIG. 2 shows a plot of PbO/PbS ratio vs. Cu content of white metal in a copper converting process.
  • FIG. 3 shows the calculated partial pressure exceeding 10 -6 bar during the slag production phase versus the amount of air injected per ton matte and the copper content of the matte in a copper converting process.
  • FIG. 4 shows calculated composition of the gas phase in the copper making stage versus the amount of air being injected per ton matte during the initial slag blowing stage.
  • FIG. 5 shows a plot of intensity of SO 2 absorption vs. wavelength in a copper converting process.
  • FIG. 6 shows an emitted spectrum from a converter flame in a small resolution in the interval 200-700 nm in a copper converting process.
  • FIG. 7 shows a spectrum of a hot spot in the wave length interval 200-300 nm in a copper converting process.
  • FIG. 8 shows a plot of sodium lines in absorption and emission in a copper converting process.
  • FIG. 9 shows the changes in relative intensities of two emissions of one product at various temperatures in an iron/steel production process.
  • Spectrophotometric measurements of a copper converter flame were carried out using a modern optical system capable of measuring either a complete spectrum or part of a spectrum with a high resolution in a very short time period, typically 10 ms.
  • a Jarrel-Ash model 1233 spectrometer containing three interchangeable gratings was used to disperse the incoming light.
  • the gratings covered the spectral range 3200 ⁇ , 800 ⁇ , and 200 ⁇ (and had 150, 600, and 2400 grooves per mm).
  • the measurements were carried out in the wave length range 200 to 800 nm, and more particularly in the range 400 to 650 nm.
  • the resulting spectra were recorded on a PARC model 1421 detector with 1024 diodes placed in a row in the exit plane of the spectrometer.
  • the detector included an image intensifier.
  • a PARC model 1460 OMA (Optical Multichannel Analyser) console was used to display the data, and spectra were stored on floppy discs for further processing and evaluation.
  • the system was used both for emission measurements, when the light from the converter flame was focused on the entrance slit of the spectrometer, and for absorption measurements when light from a Xe-lamp after having passed the flame was fed through an optical fibre to the entrance slit.
  • FIG. 1 shows parts of the spectra emitted during slag and copper making stages.
  • the spectra consist of a continuous background caused by Planck radiation from particles in the flame and contributions from gaseous elements. It turned out that the dominating gaseous emitter during the slag phase was PbS while during copper making phase PbO dominated the emission spectrum. Close to the end of the slag phase one could observe that the emission spectrum started to change from a pure PbS spectrum to a mixture of a PbS and PbO spectra.
  • FIG. 2 shows the end-point value of the ratio determined versus the copper content in the white metal (concentrated matte). When the ratio increases the copper content reaches an asymptotic value of 77.5 %.
  • the Cu content of the white metal was determined using XRF (X-ray fluorescense) determinations on a sample taken after the interruption of the process.
  • FIG. 5 shows the intensity of the SO 2 absorption versus the wave length at some different instants before the end point.
  • the metal-containing gaseous constituents which were considered in the calculations were PbS, Pb, PbO, Bi, Bi2, BiS, Zn, ZnS, As, As 2 , As 4 , AsS, AsO, As 4 S 4 , As 4 O 6 , Sb, Sb 2 , Sb 4 , SbO, and SbS.
  • FIG. 3 shows the calculated partial pressure exceeding 10 -6 bar during the slag production phase versus the amount of air injected per ton matte and the copper content of the matte.
  • the calculated variation of the partial pressures of PbO(g) and PbS(g) is in good agreement with spectrometric measurements, and show a greater increase in the ratio p(PbO,g):p(PbS,g) at matte concentrations exceeding 75% of Cu.
  • FIG. 4 shows the calculated composition of the gas phase in the copper making stage versus the amount of air being injected per ton matte during the initial slag blowing stage.
  • the white metal was supposed to contain 77.1% of Cu and 2% of the slag formed during the slag forming stage were supposed to be suspended in the white metal. From about 60 Nm 3 air per ton of initial matte metallic copper starts to form and from that point the p(PbO,g):p(PbS,g) ratio remains unchanged during the whole process with a value of about 2.6 in a quantitative agreement with the optical observation.
  • the determination of the end point of the slag forming stage and copper making stage in the converting process is today mainly dependent on skillful operators.
  • Computer programs for the calculation of blowing time, addition of sand, and heat balances exist.
  • the reliability of the calculated blowing time is dependent on the amount of Cu left in the converter from a previous cycle, the amount of slag in the matte added, the composition of scrap added and recirculated slag from different steps of the process, as well as the oxygen efficiency. All these parameters thus influence the process to a greater or lesser extent and thus have to be estimated by the operator.
  • the calculated blowing time can thus be used as a coarse guide only to determine the end point and the final decision is today in the hands of the operator.
  • the light emitted from the process can be used, after spectrometric determinations and analysis, to exactly determine the end point of the process steps, independent of the skill of the operators.
  • the process can also be closed to a greater extent which leads to less emissions of sulphur dioxide through the ventilation system of the plant.
  • the invention is thus based on a technique where, in this case, the end point of the slag producing phase of a copper process can be determined by measurements of the intensity ratios between the emitted light from PbO(g) and PbS(g) whereby variations in the background due to disturbances are restricted, and disturbances from variations in the total lead content are restricted as long as spectra from lead compounds can be identified.
  • the lead content in the white metal formed in the slag phase varied in the actual plant between 0.5 to 2 % by weight and even at lower concentrations the emitted light was strong enough to be detected.
  • the variations of the silicon content of the slag influences the oxygen partial pressure and thus also the PbO:PbS ratio in the gas phase. These differences dependent on variations of the silicon content are small compared with the rapid increase of the PbO:PbS ratio at the end of the slag producing phase.
  • the utilization of the present method for an exact monitoring and control of the slag producing phase at a copper process leads to potentially great advantages as the number of over blows and to early interrupted slag blows are reduced to a minimum.
  • the copper content of the white metal is 76 to 77 % after the final blow. If this step is interrupted too early the blow has to be restarted after an analysis, which takes about 20 minutes to carry through. If on the other hand one drives the copper making stage with too low Cu content there exists a considerable risk for of the formation of magnetite and an increased risk of slag foaming with a great time loss as a consequence.
  • the exact monitoring and control of the copper content is also essential to optimize the removal of impurities to the slag phase during the slag stage.
  • impurities such as Ni and Sb show an improved distribution to the slag phase at higher copper concentrations but if the blow continues above 78% of copper in the white metal metallic copper starts to form as indicated above, and this counteracts the elimination of impurities to the slag as the distribution of impurities between slag and metallic copper is more unfavorable than between slag and white metal.
  • the temperature can easily be followed in a process by recording and comparing the intensities in different emission/absorption bands from one and the same molecule and/or the width of an emission/absorption band from one and the same molecule.
  • FIG. 9 shows the changes in relative intensities of two emissions of one product of an iron/steel process, where the intensities are recorded from 1500° C. (top), and to 1650° C. (bottom). Thus there is a gap of approximately 35° C. between each recording.
  • the temperature can be easily determined by re-cording and calculating the ratios between the two intensities.
  • the use of the present invention means that open converter processes can easily be closed and thereby it is possible to radically improve the environment in and around a smelter. Further by closing the process gas collecting systems do not need to be dimensioned for the large gas volumes necessary to handle when using an open converter to remove hazardous gases leaking to the environment but can be adopted to the amount of gas which is really produced in the process.
  • FIG. 6 shows the emitted spectrum from a converter flame in a small resolution in the interval 200 to 700 nm
  • FIG. 7 shows a spectrum of the hot spot in the wave length interval 200 to 300 nm, in which spectrum the majority of the discrete structures come from atomic iron, but also atomic manganese, sodium, and potassium have been identified. Strong iron and manganese lines have been marked in FIG. 7.
  • the recordings show that the ratio Fe/Mn changes during the blow in a converter, as well as the K/Fe ratio varies considerably.
  • Ni, Cr, Mn, Mo, Al, MgO, CaO are present in the smelt, and, in particular, FeSi is present during the reduction phase.
  • Mn and Cr are present as compounds and can be easily determined.
  • the temperature in a smelter can be determined accurately, and the elementary composition of the melt can be determined in order to reach a correct alloy point. It is important in a steel making process to reach the correct concentration of carbon at the correct temperature of the melt. This can easily be achieved by means of the present invention.
  • the elementary composition can be used to control the addition of alloying metals which has become more important because of the increasing use of scrap metal, the total composition of which is very uncertain.
  • the quality of the lining layer can easily be determined by monitoring through the oxygen lance the K, Na, and Al presence in the hot spot. Particularly monitoring of the emission/absorption of Na makes it possible to check the lining.
  • the determination hereby involves a study of the intensity and shape of the absorption and emission lines of Na and K, particularly at 600, and 400 nm, respectively. Compare FIG. 8 in which graph a) shows the sodium lines in absorption only, and graph b) the lines as self-reversed emission lines.
  • the method can use different measuring methods such as direct optical measurement using conventional optics, but also modern fibre optics whereby process control based on the conditions underneath a protecting and cooling slag layer is technically possible.
  • a protecting and cooling slag layer may sometimes change the status of the atom or molecule on which a determination is based and thus it may be of utmost interest to follow the conditions at the actual reaction site. This situation is encountered for example, in a steel melt during oxygen blowing.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Analytical Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Automation & Control Theory (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Immunology (AREA)
  • General Physics & Mathematics (AREA)
  • General Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Pathology (AREA)
  • Plasma & Fusion (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
  • Furnace Details (AREA)
US07/772,115 1987-08-20 1988-08-17 Metallurgical controlling method Expired - Fee Related US5125963A (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
SE8703233 1987-08-20
SE8703233A SE458529B (sv) 1987-08-20 1987-08-20 Foerfarande foer kontroll och styrning av pyrometallurgiska processer medelst optisk spektrometri
SE8800321A SE8800321D0 (sv) 1987-08-20 1988-02-02 Metallurgisk styrmetod
SE8800321 1988-02-02

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US (1) US5125963A (sv)
EP (1) EP0328613B1 (sv)
JP (1) JP2761643B2 (sv)
KR (1) KR960000057B1 (sv)
AT (1) ATE84320T1 (sv)
AU (1) AU593999B2 (sv)
CA (1) CA1303861C (sv)
DE (1) DE3877345T2 (sv)
FI (1) FI95148C (sv)
SE (1) SE8800321D0 (sv)
WO (1) WO1989001530A1 (sv)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USH1925H (en) * 1998-08-18 2000-12-05 The United States Of America As Represented By The Secretary Of The Navy Apparatus and method for monitoring steel decarburization by remote flame emission spatial imaging spectroscopy
US6165248A (en) * 1999-05-24 2000-12-26 Metallic Fingerprints, Inc. Evaluating precious metal content in the processing of scrap materials
WO2015085893A1 (zh) * 2013-12-13 2015-06-18 金隆铜业有限公司 铜转炉吹炼自动控制系统
US11692239B2 (en) * 2016-06-10 2023-07-04 Centre National De La Recherche Scientifique (Cnrs) Process and system for plasma-induced selective extraction and recovery of species from a matrix

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8551209B2 (en) 2010-10-13 2013-10-08 Unisearch Associates Inc. Method and apparatus for improved process control and real-time determination of carbon content during vacuum degassing of molten metals
CN103645694B (zh) * 2013-11-28 2017-03-15 金隆铜业有限公司 Ps铜转炉吹炼过程智能决策与终点预报方法及装置
CN110809629B (zh) * 2017-06-30 2022-04-05 杰富意钢铁株式会社 转炉操作的监视方法及转炉的操作方法
KR101981429B1 (ko) 2018-05-02 2019-05-23 모링가 농업회사법인 주식회사 모링가 울금환 및 이의 제조방법
JP6954262B2 (ja) * 2018-12-28 2021-10-27 Ｊｆｅスチール株式会社 転炉の操業方法

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3513307A (en) * 1965-11-29 1970-05-19 Canadian Patents Dev Copper smelting converter having an infrared analyzer for determining the concentration of sulfur dioxide in the flue gas
US4008075A (en) * 1973-12-20 1977-02-15 Boliden Aktiebolag Autogenous smelting of lead in a top blown rotary converter
US4222506A (en) * 1976-11-17 1980-09-16 Sumitomo Metal Industries Limited Molten steel outflow automatically controlling device
US4251269A (en) * 1977-09-10 1981-02-17 Nisshin Steel Co., Ltd. Method for controlling steel making process under reduced pressures
US4296086A (en) * 1978-12-15 1981-10-20 Johnson, Matthey & Co., Limited Monitoring process and apparatus
US4345746A (en) * 1979-11-07 1982-08-24 Arbed S.A. Apparatus for refining ferrous melt with slag conditioning
US4425160A (en) * 1982-11-23 1984-01-10 Gnb Batteries Inc. Refining process for removing antimony from lead bullion
JPS60255911A (ja) * 1984-05-31 1985-12-17 Kawasaki Steel Corp 連続精錬における精錬剤供給量の制御方法
US4651976A (en) * 1984-04-27 1987-03-24 Nippon Steel Corporation Method for operating a converter used for steel refining

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE686256A (sv) * 1965-10-04 1967-02-01

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3513307A (en) * 1965-11-29 1970-05-19 Canadian Patents Dev Copper smelting converter having an infrared analyzer for determining the concentration of sulfur dioxide in the flue gas
US4008075A (en) * 1973-12-20 1977-02-15 Boliden Aktiebolag Autogenous smelting of lead in a top blown rotary converter
US4222506A (en) * 1976-11-17 1980-09-16 Sumitomo Metal Industries Limited Molten steel outflow automatically controlling device
US4251269A (en) * 1977-09-10 1981-02-17 Nisshin Steel Co., Ltd. Method for controlling steel making process under reduced pressures
US4296086A (en) * 1978-12-15 1981-10-20 Johnson, Matthey & Co., Limited Monitoring process and apparatus
US4345746A (en) * 1979-11-07 1982-08-24 Arbed S.A. Apparatus for refining ferrous melt with slag conditioning
US4425160A (en) * 1982-11-23 1984-01-10 Gnb Batteries Inc. Refining process for removing antimony from lead bullion
US4651976A (en) * 1984-04-27 1987-03-24 Nippon Steel Corporation Method for operating a converter used for steel refining
JPS60255911A (ja) * 1984-05-31 1985-12-17 Kawasaki Steel Corp 連続精錬における精錬剤供給量の制御方法

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USH1925H (en) * 1998-08-18 2000-12-05 The United States Of America As Represented By The Secretary Of The Navy Apparatus and method for monitoring steel decarburization by remote flame emission spatial imaging spectroscopy
US6165248A (en) * 1999-05-24 2000-12-26 Metallic Fingerprints, Inc. Evaluating precious metal content in the processing of scrap materials
WO2015085893A1 (zh) * 2013-12-13 2015-06-18 金隆铜业有限公司 铜转炉吹炼自动控制系统
US11692239B2 (en) * 2016-06-10 2023-07-04 Centre National De La Recherche Scientifique (Cnrs) Process and system for plasma-induced selective extraction and recovery of species from a matrix

Also Published As

Publication number Publication date
FI891801A0 (sv) 1989-04-14
KR960000057B1 (ko) 1996-01-03
CA1303861C (en) 1992-06-23
DE3877345T2 (de) 1993-05-06
AU2324188A (en) 1989-03-09
WO1989001530A1 (en) 1989-02-23
KR890701780A (ko) 1989-12-21
EP0328613B1 (en) 1993-01-07
FI95148B (sv) 1995-09-15
FI95148C (sv) 1995-12-27
DE3877345D1 (de) 1993-02-18
AU593999B2 (en) 1990-02-22
JPH02500672A (ja) 1990-03-08
EP0328613A1 (en) 1989-08-23
FI891801L (sv) 1989-04-14
JP2761643B2 (ja) 1998-06-04
ATE84320T1 (de) 1993-01-15
SE8800321D0 (sv) 1988-02-02

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